People who call 9-1-1 to report an incident sometimes cannot speak or make themselves understood for physical or safety reasons. This type of call is known as an Open Line, where the call is answered by the 9-1-1 facility but there is no intelligible voice or very difficult to understand speech. Because of this, emergency call-takers have to make difficult subjective decisions regarding how to best assist the caller. This may be dangerous for first responders since they have no idea what they might find at a scene. It also might be dangerous for the caller, who may not get the resources he or she needs in time. Additionally, such Open Line calls may result in wasted resources since these types of calls may require police, fire, and medical dispatch for safety reasons, even if only one type of dispatch or lower level of assistance is needed.
In response to the Open Line problem, some Public Safety Access Points (PSAPs) have implemented protocols that help the call-takers make decisions regarding how to handle such calls. However, there currently are no automated tools available to help these individuals glean additional information from the background or non-verbal portions of the call.